The Louisiana Democrat. [volume] (Alexandria, La.) 1845-1918, 1887-06-22
A SUN CLUSTER.
Speculations Concerning a Won
derful Phenomenon.

In the constellation Hercules there i.
acompact star cluster well-known t.
owners of powerful telescopes as one
of the most interesting and wonderful
phenomena to be found in the heavens.
To the naked eye it looks like faint
star In the telescope it appears as a
spherical mass of stars, with short
Struggling streams, also composed Of
stars, radiating from it. William
Herschel computed the number of stars
in this cluster at not less than IA, 900.
In the center they appear so COM
pressed that it is impossible to count
them.
Of course every one of the members
of this starry swarm is sun, and as
tronomers have sometimes piqued
their imagination by wondering what
must be the condition of things pre-
vailing in such system of suns, and
what results flow from the inevitab BILE
laws of gravitstion there. Could in
habited worlds exist in sun cluster?
A calculation of the probable size of
the stars in the cluster in Hercules,
and of the average distance which
separates one from another, has just
been made in England by Mr.. j. E.
Gore. He concludes that they have an
average diameter of 5000 miles, and
that the distance from any star in the
cluster to the next star is 5000, 900, 900
miles.
Taking Mr.. Cores figures as being
probably as near the truth as we can
get, little consideration will give us
some very interesting results. If the
stars in question are only $4,000 miles
in diameter, the surface of each pos
sesses an area about one-quarter as
great as that of the planet Jupiter.
Their distance apart as calculated by
Mr. Gore, is more than twenty times
the present distance of Jupiter from
the earth. Just now Jupiter shines
brighter than any star in our sky,
with the exception of Venus. If its
disk were reduced to one-quarter of
Its actual size, and it was removed
twenty times as far away as it is, it !
would become invisible to the naked
eye.
But Jupiter shines only by reflected |
light, while the stars. being suns, shine
with their own light which is enor-
mously more brilliant than that of a
planet. So if we wish to get an idea
OF the amount of light shed by one of
these clustered suns in Hercules, we
must put a body that shines after the
manner OF the sun in the place of Jupi-
ter Now, if we should remove the
sun to distance of 9, 900, 900, 900 miles,
Or roughly a hundred times as far
away as it actually is, it would send
US only one ten-thousandth part
OF the light that we now re-
eeiVe from it. Then if we
should reduce it to diameter OF 45, 900
miles, equal to that of the stars in the
hercules cluster, its light would be re-
duced about $50 times more. so that If
would then shine to us with only one
'nree-million six d-thousandth
part OF the light that it now sheds up
on d the earth. This, then, supposing
lnat the intrinsic brillancy of the stars
IS Inc same as that of the sun, would
represent the amount of light that one
u the stars in the cluster sends to its ,
next neighbor.
!, But in order to get conception of
.ne appearance that such star would
present. we must compare its light
'i'h mat OF the stars in our sky. This
involves good deal of UNI
owing to the great differ =,
'nces IN the various estimates that have {
'een made of the brightness of the a
'ars as compared with the sun or a
loon' Still we can probably get near a
,nough to the truth for our purpose. v
axe the bright star Sirius, the most a
Fhhant fixed star in the heavens. ANY
ne who wishes can see it in the south s
IN heavens early in the evening at
MS season. Various estimates of the O
ght OF Sirius have made it t
ON one twenty-thousand- millionth a
to about one five o
lousand-millionth of the SUMS light. b
oppose we adopt the latter figure as G
sins the most favorable to Sirius. K
men comparing this with the fraction il
presenting the light of star in Her a
iles as seen from its nearest neigh e,
'fs In comparison with that of the 81
H. namely, one three-million-six- b
4aared-th1ousandth, we find that the d